1. Field of the Invention
The present invention relates to a light source unit.
2. Description of the Related Art
Among types of light source units to emit light, some light source units emit light in a specialized manner in use of the light source units. Specifically, in conventional light source units, some light source units emit linear light. For example, a light source unit includes a columnar light guide member and a light emitting diode (LED) arranged on one end of the columnar light guide member, to emit linear light such that the light emitted from the LED is guided in the lengthwise direction of the light guide member so as to cause the light to be output through the outer circumferential surface of the light guide member (for example, see Japanese Patent Application Laid-open No. 2012-38470). In this case, the LED generates heat at the time of lighting. To cope with the heat, a heat dissipation member is provided along the light guide member extending in one direction and the heat dissipation member holds the light guide member. With this constitution, the heat generated at the time of lighting of the LED can be dissipated while holding the LED with predetermined strength ensured.
When a plurality of LEDs and light guide members are provided and linear light is emitted from the respective light guide members, the LEDs need to be arranged on end portions of the respective light guide members. When the LEDs are arranged on the end portions of the respective light guide members, assembly of the light source unit and an exchange operation of the LEDs tend to be troublesome. Moreover, the arrangement of the LEDs on the respective light guide members requires provision of the heat dissipation members for the respective light guide members, which can also result in a difficult and complicated assembly operation of the light source unit.
In contrast, when one heat dissipation member is provided for a plurality of light guide members and the one heat dissipation member holds the light guide members, regions of the respective light guide members that are covered by the heat dissipation member are small. In this case, heat dissipation performance by the heat dissipation member can be lowered in comparison with the case where the heat dissipation members are individually provided for the respective light guide members and strength when the heat dissipation member holds the light guide members can be lowered. Thus, when the light guide members are provided in plurality as described above, it is extremely difficult to ensure assembly performance and heat dissipation performance while ensuring strength when the light guide members are held.